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What Is a Smartphone

by Michael Juntao Yuan
A Smartphone combines the functions of a cellular phone and a handheld computer in a single device. It differs from a normal phone in that it has an operating system and local storage, so users can add and store information, send and receive email, and install programs to the phone as they could with a PDA. A smartphone gives users the best of both worlds--it has much the same capabilities as a handheld computer and the communications ability of a mobile phone.

In this article

  1. Mobile Phones and PDAs
  2. Emergence of the Smartphone
  3. Developing Smartphone Applications
  4. So, What Is a Smartphone?

The word "smartphone" is defined as "a mobile phone that incorporates a PDA (Personal Digital Assistant)" by the Oxford American Dictionary. So, by definition, a smartphone is a converged, multipurpose device. Historically, mobile phones and PDAs have evolved along very different paths. Mobile phones started as dumb voice terminals while PDAs started like mini-PCs. Before we start discussing smartphones, let's have a brief review of how mobile phones and PDAs got to where they are today.

Mobile Phones and PDAs

The original mobile phone was a wireless telephone device primarily for voice communications. Like any other telephone, the mobile phone is only useful when it is hooked into a network and has a service agreement with an operator (a.k.a., a carrier). As a result, mobile phone technology is tightly coupled with the underlying wireless network technologies and the available network services. So far, the wireless network and devices have gone through several generations:

For PDAs, the story is much simpler. Unlike mobile phones, PDAs do not require subscription-based network services. They are standalone minicomputers, pretty much like PCs before the internet.

The first generation of successful PDAs are Palm Pilots. They primarily function as electronic organizers with support for address books, calendars, email, notes, etc. The PDA only occasionally needs to connect to a companion PC (pairing) for "synchronization." For instance, a PDA can be synchronized with your PC address book, calendar, and email inbox, via a USB or serial cable. Newer PDA models can also connect to PCs wirelessly via Bluetooth, or connect to the internet via WiFi.

A key characteristic that makes PDAs "smart" is that they are programmable. You can use regular computer-programming languages such as C, C++, Java, and BASIC to write PDA applications. In fact, thousands of applications, from medical dictionary to music players to web browsers, have been written for Palm and Microsoft PocketPC PDAs. Those applications are essential for the wide adoption of PDAs. In addition to user-installed software, PDAs can also work with an array of hardware add-ons. For instance, you can attach a thumb keyboard or a GPS unit to a PDA.

Emergence of the Smartphone

As mobile phones and PDAs evolved, it became obvious that the connectivity of mobile phones, and the programmability and extensibility of PDAs could nicely complement each other. From the user's point of view, carrying a single device that does everything on the road is much better than having to carry multiple devices and manage their synchronizations. Addressing those needs, smartphones started to emerge. Smartphones can be built from a PDA or from a mobile phone.

A smartphone can be a PDA with added network connectivity and phone functionalities. Representative models in this category include the Microsoft PocketPC Phone and Palm Treo. They target existing PDA users. Those smartphones have large touch screens, fast CPUs, and thumb keyboards (or handwriting recognition systems). However, they are also relatively bulky, have poor voice quality, and short battery life. The PDA-style smartphones are popular among business users who desire the computing power and don't mind much about the inconvenience.

A smartphone can also evolve from a regular mobile phone. In this case, it is a mobile phone with a programmable brain. Representative models of those smartphones include all Symbian smartphones from Nokia, Sony Ercisson, Motorola, as well as Microsoft's Windows Mobile smartphones. They target the general consumers. This type of smartphone excels in voice calls and text messaging, but is less effective for computational intensive tasks or applications that require a lot of typing. Power users can find many advanced PDA features behind the simple UI of these smartphones.

The term smartphone is best known as the marketing names for Nokia Series 60 devices, Microsoft Windows Mobile devices, and Palm PDA phones. But in fact, the scope of smartphones is much greater than those devices. For instance, the vastly popular Nokia Series 40 phones, which have sold more than 250 million units, perfectly match the smartphone definition. If you're buying a new mobile phone today, you are probably getting one of the programmable smartphone packed with PDA-like features.

The Smartphone is hugely successful in the marketplace. Nokia alone ships more than 10 million Symbian-based smartphones (Nokia Series 60 and 80 devices) every year. And the annual growth rate of the smartphone market has been over 100 percent. The "mobile phone-style" smartphones far outsell the "PDA-style" smartphones, despite their similar price points. In the U.S., the once large PDA market has been almost completely squeezed out by smartphones. What makes smartphones so successful? Let's check out some core smartphone features.

What Can a Smartphone Do?

Smartphones are very useful to busy individuals in modern society. However, a challenge for smartphone users is to discover exactly what your device can do, and actually take advantage of it. Many people I know just use their $500 smartphones as simple mobile phones for voice communications. That is because they never explored their smartphones beyond the simplistic "phone" user interface, or never had the time to research third-party software applications for the device. But a little time spent on exploration could mean big productivity gains and a much better return on your investment in the smartphone. In general, smartphones have the following key features.

(Note: Most smartphone features and techniques covered in this section are discussed in detail in the Nokia Smartphone Hacks book. Similar features are also generally available on non-Nokia smartphones.)

Manage Voice Calls

Despite all the digital gadgetry and data applications, for most users, the smartphone is still a mobile phone. Making voice phone calls is still the number one use of smartphones. A lot of smartphone features are focused on making phone calls easier. For instance, you can use the smartphone user interface to manage multiple concurrent calls or conference calls on the phone; change the ringing option, including ringtones and alert images, based on the caller or the caller group; record phone calls to digital files and save them to computers; and make phone calls directly from wireless internet web pages.

Third-party software programs for call management are also widely available for smartphones. For instance, some programs allow you to change phone ringing options based on your location; other programs track minutes usage in your calling plan, with support for peak hours, family-free numbers, nonstandard billing periods, and so on.

Enhance the Computer

Most of us already have laptop or tablet computers. Why do we need to carry another minicomputer, the smartphone, with us? Well, it turns out that a smartphone can nicely complement the computer you already have. The computer connects to the smartphone via Bluetooth or data cables.

For instance, you can use the smartphone to exchange business cards with other people in a meeting and easily synchronize them to the computer. The computer can use the smartphone as a data modem and share the wireless internet connection when WiFi is not available. With the right software, the smartphone can be used as a remote control for the computer during presentations or media playback.

Increase Productivity

With many business applications available on the smartphone, you can significantly increase your productivity while you are traveling or away from your office. The most obvious business productivity application on the phone is email. A smartphone can access email via a variety of methods, including standard SMTP/POP servers, corporate email servers, or mobile messaging proxy services. Email attachments for common corporate documents, such as Word and Excel documents, are also supported (both read and write). Smartphone email clients can meet business users' very diverse email needs.

The smartphone also helps you stay on instant messaging (IM) services. You can stay connected with your AOL, Yahoo, and MSN buddies while you are on the go. For email and messaging applications, an easy-to-use keyboard is essential. Some smartphones have built-in thumb keyboards or can work with portable Bluetooth keyboards, as long as the appropriate software driver is installed. Even for the numerical keypad-only smartphones, the device software can assist text input with support for predictive input methods like T9, and text cut/paste across applications.

Access Web 2.0

Smartphones can access not only WAP contents on the wireless internet, but also regular HTML web sites. A smartphone typically has relatively large and color screens to render web contents. Smartphone browsers (e.g., the Opera browser) can automatically reformat the HTML page for small screen display. But perhaps even more important is that smartphones can access Web 2.0 contents such as blogs, RSS, podcasting, P2P social networks, etc. For instance, you can post stories to your own blog or podcasting site at the time when the story happens, and read other people's P2P contents to stay updated all the time. To parse RSS and other Web 2.0 contents on the smartphone, you would probably need to install additional software or work with special mobile gateway servers.

Integrate Location Information

Location-based services are touted as the next killer application for mobile computing. A smartphone can obtain its current location by integrating a GPS receiver or connecting to existing portable GPS receivers. If a GPS is not available, some smartphones can obtain location information by triangulating nearby cellular service towers, or simply identifying the cell ID of the current service tower. Using the location information, you can tag your blog/photo postings with your location, search businesses or points of interests in your vicinity, get driving directions, or even change the phone's settings automatically depending on where you are (e.g., when you are at home, the phone would not ring when your boss calls).

Another type of location service is the ability to form ad hoc local networks. Using Bluetooth technology, some smartphone applications allow you to detect people in your vicinity and you can initiate a personal contact when someone's published profile meets your interests. Some businesses (e.g., retail stores) have Bluetooth services to send coupons or even multimedia contents to your smartphone while you are visiting.

Share Multimedia Contents

Today's smartphone typically has a built-in digital camera and a sound recorder. You can not only take still photos, but also movie clips with the smartphone. With the prevalence of MMS services, you can easily send the photos and movie clips to other smartphones or friends' email addresses. With some additional software, you can post those contents to your blog or photo sharing/printing web sites like flickr.com. Another approach for multimedia sharing is to simply download the camera phone photos and movie clips to your computer via Bluetooth, and share them from there.

In addition to multimedia-contents capturing, the smartphone can also be used as a networked multimedia player. You can get contents from your friends over MMS or email. You can also watch TV or other wireless contents via streaming media players like the RealOne player or Microsoft MediaPlayer.

Developing Smartphone Applications

Smartphones would never be so successful without thousands of third-party software applications. If you are a computer programmer, you can write smartphone software as well--either to meet your own needs or even to sell for a profit. Most smartphones can be programmed with standard programming languages and APIs. Here is a list:

So, What Is a Smartphone?

Smartphones are converged devices that combine mobility, connectivity, and programmability. They are quickly taking over the market for mobile phones and PDAs. In fact, if you purchased a new mobile phone in the last year or so, there is a good chance that you already know a smartphone. You just need to explore it and make best use of it, if you have not done so already. For computer programmers, smartphones represent great opportunities for developing new applications or just hacking for fun.

Michael Juntao Yuan specializes in lightweight enterprise / web application, and end-to-end mobile application development.

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